1. Field of the Invention
This invention relates generally to a method and apparatus for the percutaneous introduction of a paddle style lead into nervous system structures of a patient including into the spinal canal or other nervous system structures, central or peripheral. More specifically, this invention relates to the percutaneous introduction of a paddle style lead into the spinal canal or other nervous system structures, central or peripheral, through a needle with an oblong cross section.
2. Description of Related Art
Spinal cord stimulation is used to treat a multitude of disorders including multiple sclerosis, spinal cord injury, cerebral palsy, amyotrophic lateral sclerosis, dystonia, torticollis and other neurological disorders. Spinal cord stimulation is also useful for treating pain including intractable malignant and nonmalignant pain. Neural stimulation electrodes and leads implanted in a patient in the epidural space of the spinal canal or other nervous system structures, central or peripheral, stimulate selected locations of the spinal canal or other nervous system structures for treatment of pain and various conditions.
Surgically implantable paddle style leads, or flat leads, and percutaneous insertable wire leads for the spinal canal have been in use for some time. These paddle style, or flat leads, and wire leads are used for electrical stimulation of neurons in the spinal canal. Two types of leads are generally used for spinal cord stimulation: 1) wire and 2) paddle.
Typically, a wire lead is introduced into the spinal canal using a needle and a stylet assembly. The needle and stylet are inserted into the spinal canal area between adjacent vertebrae until the tip of the needle and stylet are advanced into the epidural space of the spinal canal area. The stylet is withdrawn and a wire lead is inserted through the open area or lumen of the needle and into the epidural space to a selected location adjacent to the spinal cord. Some needle and stylet assemblies have a curved distal tip to facilitate introduction of the lead at an angle to the axis of the lumen portion of the needle. The needle typically has a side opening or orifice at its distal end for insertion of the lead into the selected location of the spinal canal. In some assemblies, the stylet may fill the entire lumen cavity including the side opening of the needle to prevent the collection of tissue in the lumen cavity during insertion of the needle. The stylet can also provide rigidity to the needle body for use during insertion.
Current needle technology requires that all leads be of a circular cross section in order to be placed through the lumen portion of the needle into the epidural space. Needles used for insertion of the wire leads typically have a circular cross section between 14 and 18 gauge.
The paddle style or flat leads are generally rectangular shaped flat paddles that must be surgically implanted. To introduce a paddle style lead into the epidural space percutaneously using needle insertion, the paddle lead must be rolled to a circular shape to slide through the typical circular cross section needle. The method of rolling the paddle lead and inserting through a needle and unrolling the paddle style lead has not been perfected for use. The only way to insert a paddle style lead is by a surgical procedure known as a laminotomy, a laminectomy, or similar surgical procedure. Because the paddle style lead must be surgically implanted, anesthesiologists may not perform the procedure.
Accordingly, there remains a need in the art for a non-surgical method of inserting a paddle style or flat lead into the spinal canal area.
The present invention recognizes and provides a solution to the problems associated with the percutaneous introduction of paddle style leads. The invention provides a unique needle for percutaneous insertion of a paddle style lead into the spinal canal area or into other nervous system structures, central or peripheral,. Briefly, the present invention comprises a needle for percutaneous insertion having a lumen with an oblong cross section sized to receive a paddle style lead.
Accordingly, an object of the present invention is to provide an apparatus for percutaneous insertion of paddle style leads that may be utilized by both surgeons and anesthesiologists. Current needles used for introduction of leads for electrical stimulation have a round cross section. Paddle style leads cannot be inserted through these needles. The paddle style lead must be inserted by a surgeon performing a laminotomy, a laminectomy or similar surgical procedure where the surgeon cuts open the tissue and then slides the lead into the proper position. This novel invention uses a needle having a lumen with an oblong cross section. A flat, paddle style lead based on current lead technology is passed through the oblong cross section of the lumen in this needle for introduction into the spinal canal area or other nervous system structures, central or peripheral. This invention allows for percutaneous insertion through a needle without performing the above mentioned surgical procedures.
Another object of this invention is to provide a less traumatic procedure for patients during the implantation of paddle style leads for treatment. Surgical introduction of leads for electrical stimulation is traumatic for patients. Insertion of leads for electrical stimulation utilizing an oblong needle that is inserted near the spinal column or other nervous system structures, central or peripheral, is less traumatic for patients than surgery where the surgeon must cut the tissue open and then slide the lead into the proper position.
The full range of objects, advantages, and features of the invention are only appreciated by a full reading of this specification and a full understanding of the invention. Therefore, to complete this specification, a detailed description of the invention and the preferred embodiments follow, after a brief description of the drawing wherein additional objects, advantages and features of the invention are disclosed.